This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
The above is from the book I am reading these days.It says"gives you a one if the forth bit from the right in the binary representation of n is 1 and 0 if not".
Can you explain this a bit further. Are the operators &, |, ^, ~ bitwise operators? I thought >>>, >> are the bitwise operators. Where can I get some more information about bitwise operators? Why do we have bitwise operators, during what situations are they used?
See Java Tutorial - Bitwise and Bit Shift Operators.
With respect to your example, the & operator compares two values bit by bit (bitwise), and returns a 1 if both values have a 1 in that position. In other words, if the first value has a 1 in that position AND the second value also has a 1 in that position. Otherwise, it returns a 0.
For example, suppose you have two binary values: 1100 and 1010. Applying the & operator to these values would result in 1000, because the fourth bit from the right is the only position in which both values have a 1.
So consider (n&8)/8. In binary, 8 is 00001000. So if you have some other value 'n', then n&8 will result in 00000000 if the fourth bit of n is zero, or 00001000 if the fourth bit of n is one. Dividing this by 8 results in either 0 or 1 respectively -- which tells you what the fourth bit of n is.
"We're kind of on the level of crossword puzzle writers... And no one ever goes to them and gives them an award." ~Joe Strummer sscce.org